Steam generator



April 17, 1928.

A. FRANCO STEAM GENERATOR I 4 Sheets-Sheet 1 Filed Feb. 11, 11,925

April '17, 1928.

A, FRANCO STEAM GENERATOR 4 Sheets-Sheet 2 Filed Feb. 11, 1925 April 17, 1928. 1,666,128

A. FRANCO STEAM GENERATOR Filed Feb. ll, 1925 4 Sheets-Sheet 5 .34- 1 :91.9. a 3/. J2 3.1 a

53 37 3 Fay/4,

April 17, 1928. 1,666,128

A. FRANCO STEAM GENERATOR Filed Feb. '11, 1925 4 Sheets-Sheet 4 in those' cases, for I restricted room conditions the space ava l- Patented Apr; 17,

l STEAM GENERATOR} Ap lication filed February 11, '1925,seria1 No. 8,590, andin m rebru ryi 1924;

' 'Thev iresent invention has for its subject used --here1na made up by the.

fi nected to it two g g one another. By the" word matter a novel typeyofboilerg fitted with a': longitudinally fired furnace, thefurna'ce being of the ordinary type but hav ng conbanks of fire'tuloes' facing furnace as fter is "meant; the aggregate shell. I g v The-novel type of boiler is advantageous instance,

able for the boiler-and for thefurnace service is a limited one.

In the accompanying I H bodinientsjof the invention arexillustrated by'wayof example "Fig. "1 is a plan show ng a boiler two Y banks ofifire tubes arranged the of a" symmetrical double T.

2 is a cross sectlon along 22of 1 withjthe assumptlon that the hoilershell is circular in crosssection h V v Fig;i3 iis a similar cross section along 2-2 of Fig; '1 but with the assumption of a boiler shell'of oval cross section.

Figures land 5 are vertical and horizontal sections respectively illustratingin detaila boiler with flattened. sides.

- tubeslare' :either'c01nc1dent with the center-V .Figures 6; 7 and I line "of the Boiler. as Fig; 61 or staggered relative thereto 'a'sin Figs? and 8; these fig'-.{ ures also shovv 'd iffere'nt leadings of thelfurnacejwalls. I

'aFig. 9 is a? planshovving. the arrangement of thelo'comotives cabinj it also shows the bfo'iler'r in horizontal section with the longitudinal; center lines 'of'the two banks fof fire tubes staggered by afc'erta'in amount relative I tothe boilers'longitudinal centerJlin'e; ,2.

' "Fig. 10 is a vertical section of th'eisaid cabln in connection *Wltll the crosssection of the banks of tuh'es shows/flattened sides. Y v 1 Figures 11 and 12 are analogous" figures-to the two preceding, figures and illustrate in plan and} cross) secti on respectively a loco} ymotives cabin inthe case of; a'boiler-in which the longitudinal center lines of the two banks offire tubes coincide with the lon- I gitudinal center 'lineof the'locoihotive and 7:55

of the cabin; a a

furnace Proper and by Where owing 'to' dra yvings several emfv in the two figures.

8* are plans illustrating several typesof boilers", in which the longi boiler fin vvhich A'r'rmo FRANCO; or ILA ITA Y) ori in-e513, 1 1 and 15 arerilans a-ndshovv :1 5': several constructions in which the longituj-.- dinal center lines of the hanksof fire tubes do not coincidewiththe center line or the I oo 1 boiler and in which the two? 'internalfurnace Walls'show different arrangements."

Fig. 1 6 is a section thro'ugh 16-516 'of Figi, 14 with'the assumption'that-the' two'internal walls of the furnace'close on 'each other g a v a siini'lar section'f'through 16- 16 inFig.f145, with the assumptionthat 1 the two saidlinternalflwallsiclosejon eachaloiovethe grate. Figure "17* is" otherat furnacelevelg 19 and-QO-Shovv thej'loconiotive icahin in plan; the looilerjbeing di-fierentl y arranged --In Fig. 1, 1 is the naee walland 3 th'e'fu'rnaceshell;*

The straight lines w -a, and

tubes 41 and 5 'with their fire tubesffi and? -b''b are the- 1 cross and l'ongitudinal' -center lines respectively of the boilerfg 1 C The furnace-l towhi'ch bothloanksof fire firing doors rnay be reduced tofia single one;

the headers-.18 and 9 may be atright angles "ri -11's" is asectionithroughi18181in' TO. a Fig.l5fwithWateratubes-instead of theme Y aforementioned internal furnacefwallsj respectively are i' 'conne'c'ted; has-jits c'ross 1 headers 8 and 9 'e'xtendedja sufficient distance j to the two side'sto provide for coal firing doors 10; According t0, requirements, these 1 to thehorizontalgeneratingfllinesj'of the two. banksof fire tubesi i and 5as-shown fori'n-- if 1 stanceon'Fig. 1, or they ma y lieat'di-ff'erent I angles relatively to the said generating lines g y The" banks of tubesfrna'y-be,cylindrical in section as show'nion' FigLQQor their cross as shown for instance in Figures 6f7 and 8-.

Section may b fl t ned, Sides as "per 1 n. the

means of specialjstays -11,that"a re shown in 1.

the shell of the banks 4 and 57.}1As mayf be seen from'Fig; 4, the stays 11 have'circular apertures ll fOIjIIlG d fin thern of sufficient 1 latter case the" irregular form "of I the'flat or"approximatelyflatsides of- -the I v banksof'fire tubes 4 and 5;can be obtained I I either by means of the ordinary stays ,orby

16 may not coincide with 0-0 and lie at a certain distance from it.

Figures 9, 10, 11, and 12 illustrate byway of example the application of a. boiler to a locomotive, with banks of fire tubes either coaxial with the boiler as in Figs. 11 and 12 or non-coaxial as in Figs. 9 and 10;

- The surface 19, 20, 21, 22, 23, and 24 with lozenge hatching give an idea of the cabin space available for the fireman for firing the boiler and handling the firing'tools'.

The'surfaces25, 26, 27, 28,29, and 30 give an idea of the space available for the coal bunkers; suitably inclined planes. cause the coal .to descend by itself within reach of the mans shovel without the man being obliged to turn himself in order to fill the shovel with'coal;

Ascompared withthe boilers :used heretofore, the novel locomotive boiler secures the following advantages:

1. Boilers with large heating surface and large gas passage sections can be installed in locomotives where only a restrictedspace is available for them; besides, more than one man can be employed for the firing, each man having considerable space at his disposal for the fire service. The men can therefore keep the air passages between the gratebars clean from slag, the checking of such passages notoriously being one of the main causes limiting the time periods during which the locomotive can be kept in service, the men not being able to simultaneously perform'the double duty of maintaining the furnace-well fed with coal and keeping the grate properly clean.

2. Suitable accommodation is provided for the firing tools alongside the shell of the banksfof fire tubes. These tools can be supported and balanced along the cabin by means of a suitable movable rest; accordingly heavier tools which are less liable to be impaired by fire can-be employed without undue eXertion and fatigue on the part of the fireman,

such tools being more fit than thoseusedat present to overcome the resistance that is often met with in the removalofslag.

3. The stoker has the coal within easy reach of his shovel, whereas in the present locomotives he is obliged to turn himself in order to fill the slmvel with coal. The modifications according to Figs. 13

to 20 relate to the furnace proper and has for its object the increase of the heating surface of the furnace as wellas the water circulation in the boiler by providing water tubes arranged in the furnace or by providing two internal walls in the furnace, in the direction of-the boilers loiwitudinal center the two banks of fire tubes as far as the water contained in said banks is concerned; in the. I

latter case,that'is where the walls'close on each other above grate level, as well as in the case of the abovesaid water tubes h eing fitted, the furnace remains common to the two banks of fire tubes both as regards the-hot gases and as regards the water contained in the two banks.

.In Figures 13, 14, and 15,31 is the boiler furnace comprising the furnace proper and its shell; 32 are the perimetral .cross. walls of the furnace; 33are the perimetral longitudinal walls of the furnace; 34 is the furnace envelope or shell; 35 are thefiredoors arranged sideways of the banks of fire tubes for the longitudinal firing. of the boiler. r f i '36 are'the furnace inside walls (Figures 13 and 14) built into the end wall,32 and forming an additional heating surface as well as. a longitudinal water canal by which the water space of one bank is set into communicationiwith the water space of theother bank. s

In Fig. '13 the inside walls 36' are shown of the boiler. r a

In Fig. 14 the'inside walls 36areshown inclined relative to the said center line a-a The wall arrangement according to Figures 13 and 14 is'merely given by way of example.

Figs. 15 and 18 are a plan and vertical section respectively showing by way of example a collector 37 of any desired shape (for instance D-shaped) built-into the furparallel to the longitudinal center line wa.

nace cross walls 32at grate level. The boting on each other at a distance b above I the grate level, and the latter one in the case of the walls 36 reaching down to the level of the grate-supporting frame like the walls 33 and 34. I

42, and 43 in Figures 19 and 20 are the outlines in plan that cannotv be exceeded according to the railways loading gauge.

0c and d-d in Figures 19 and 20 are 7 the crossand longitudinal center lines respec tively of the locomotive; e e are the longitudinal center lines of the banks of fire tubes;

44: are the said banks for firedoors arranged sideways of boiler.

In Fig.

In Fig. .20 its cross center the boiler. is

line f' f and its longitudi- I nal center line g-g lie at a certain angle w h-, inhorizo'nt 1' plane,

with the locomocZ-'cZ respectively.

tive center lines c'-0- and ascertained the Having now described and nature of my invention and inwhat manner "the same is to beperformed, I declare: that -what I claim is:

'1. A boiler comprising, provided with cross walls, 7 fire tubes mounted in either cross wall of :said furnace and extendingi parallel to the boiler axis, said furnace cross walls having ,provided with cross walls, tubes mounted in either axis, said furnace being combustion chambers V longitudinally extending partitionwall.

2 tubes mounted in either cross wall of sai 'portions pro ecting"laterally of' said ,tube

banks, said portionsprovided vwith openings for longitudinal firing.

2. A boiler comprising,

' and a bank of. fire cross wall of said and extending par divided into separate by .a substantially furnace 3. A boiler comprising, a central-furnace rovided with cross walls, furnace and extending parallel to the boiler axis, the water space tion chamber.

provided with cross walls, tubes mounted 1n either cross wall ofsaid' furnace and extending parallel to the boiler the longitudinal firing of the e y 19 the cross and longitudinal cen ter lines of the boiler coincide with c c' and d+cl respectively.

. combustion chambers by a my so arranged that a central furnace and a bank of portionspro ecting portions provided With openings a central furnace v furnace," said banks of fire allel to the boilerv and a bank of fire? 'd. ing, each of said openings of said tube banks being joinedby tially longitudinally through 4, A boiler compr g;

Waterivvallv extending substan- I the combusa centralifurnacej and a bank of fire,

axis,said furnace being divided into separate extending partition wall said of saidtube banks, with openings for longitudinal firing.

5. A boiler comprising,

tubes mounted in either cross wall of said furnace parallel to and laterally from the center line ally offset, said displaced of said boiler, said fur- Y nace being divided into separate combustion chambers by a longitudinally extending parlongitudinally furnacecross walls having portions'projecting laterally" said portions provided a central furnace; v p provided with cross walls, and a bank offire I a central furnace A and a bank of ,fire 7 55 tubes beinglate lv v, f

separate combustion chambers by a long1 tudinally (extending water wall a connecting the water space of said tubelbankasaid fur= nace cross walls laterally of ,said tube banks,

' being in alinement with one of said banks of fire tubes. I i

havingportions project ng v saidfportions provided with openings for longitudinalfir- ATTILIOFRANCQ. i 

